Recently, liquid crystal displays (LCD) have been widely applied in electrical products due to the rapid progress of optical technology and semiconductor technology. Moreover, with advantages of high image quality, compact size, light weight, low driving voltage and low power consumption, LCDs have been introduced into portable computers, personal digital assistants and color televisions, and have become the mainstream display apparatus.
In liquid crystal displays, a source driver is used to convert a digital signal to an analog voltage to transmit the image signal to the display; thus, the source driver is also called the data driver. It can receive a signal from a timing controller which may be a single-end signal or a serial signal. The single-end signal may be a transistor-transistor logic (TTL) signal, and the serial signal may be a reduced swing differential signal (RSDS) or a low voltage differential signal (LVDS).
Generally, the conventional source driver transmits only one kind of signal, either the transistor-transistor logic signal or the reduced swing differential signal. Therefore, the transistor-transistor logic signal and the reduced swing differential signal sent from the timing controller require different kinds of source driver. That is, these two kinds of signals cannot use the same source driver. In making source driver circuit boards, different source driver circuits need to be formed according to the different kinds of signals needed. Consequently, manufacturing is complicated and slow due to having to prepare many materials and allocate multiple production lines.